
This is the Title of the Book, eMatter Edition
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Automated Hardening with Bastille Linux
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tend not to get enabled, period. Call it laziness or call it a logical aversion to fixing
what doesn’t seem to be broken, but many people tinker with an application only
enough to get it working, indefinitely postponing that crucial next step of securing it,
too.
This is especially easy to justify with a server that’s supposedly protected by a fire-
wall and maybe even by local packet filters: it’s covered, right? Maybe, but maybe
not. Firewalls and packet filters protect against certain types of network attacks
(hopefully, most of them), but they can’t protect you against vulnerabilities in the
applications that firewalls/filters still allow.
As we saw with woofgang, the server we hardened with iptables and then scanned
with nmap and Nessus, it takes only one vulnerable application (OpenSSH, in this
case) to endanger a system. It’s therefore imperative that a variety of security strate-
gies and tools are employed. This is called Defense in Depth, and it’s one of the most
important concepts in information security. In short, if an attacker breaks through
one defense, she’ll still have a few more to go through before causing a lot of damage.
Documenting Bastion Hosts’ Configurations
Finally, document the steps you take in configuring and hardening ...